Means for air conditioning



July 8, 1941.

v F. w. LOCKE MEANS FOR AIR CONDITIONING Filed June 20, 1938 2sheets-sheet 1 H I M 1 Wu I ll IF Inca/17b)":

cation and for physiological benefits.

Patented July 8,1941

UNITED STATES PATENT OFFICE I r 2,248,713 MEANS FOR AIR CONDITIONINGFrank W. Locke, Portland, Ores.

Application June 20, 1938,- Serial No. 214,701

6 Claims.

My invention relates to air conditioning and deals more particularlywith the combustion of odoriferous substances, disease germs, andharmful gases such as carbon monoxide that are carried by the air; withthe purification of said air by the action of ultra-violet radiation;and with the treatment of said air with ozone for purifi- Airconditioning is particularly useful in motor coaches wherein passengersare frequently crowded in close quarters and the resultant breath andbody odors, at best, are unpleasant;- and if, for example, one of thepassengers has recently eaten garlic, they become intolerable.

Also in motor coaches, the air isusually con-- taminated by unburnedfuel and lubricating oil from the motor thereof which, in gaseous form,filters into the passengers compartment thru the floor, and thru cracksaround doors and windows. These exhaust gases always contain carbonmonoxide, which is objectionable even when present in quantities toominute to cause death. On the highway, motor coaches are continuallypassing thru air laden with fumes and gases from other motor vehicles sothat any air admitted to the passengers compartment from the outside isin need of purification. Dust, and sometimes pollen, are carried inlarge quantities by the air along highways. g

The usefulness of my invention is not limited to the rendering of airmore pleasant to breathe; its action is a positive aid in the preventionof sickness. Destruction of pollen is, of course, a great boon tosufferers from hay-fever and asthma. To the extent that diseases arespread by air borne germs, said diseases are combated by myinventionwherein three well known germicides are effectively used,namely, heat, ozone, and ultra-violet radiation. Some people, whenriding in motor coaches, are subject to a form of nausea akin toseasickness. Although the primary cause of this sickness is probably theswaying motion, it is greatly aggravated by gasoline fumes and otherodors. Removal of said fumes and odors is therefore a matter ofimportance to partially heated is rendered more susceptible to theaction of ozone. I have found that the kind of electricsparkhereafterdescribed can be used efllciently in this manner if the air'is passedthru said spark at high velocity; it is not necessary for the air to bein contact with the intense heat of the spark for very long time'inorder to ignite most combustible organic substances,- or to destroybacteria, in the presence of ozone. v

A further object of my invention is to generate ozone for immediate usein purifying air by means of a spark gap quenched by a jet of said air,which spark gap provides a multiplicity of arcs which are constantlyformed and broken at high frequency over a wide area. The conversion ofatmospheric oxygen to ozone requires voltage sufficiently high to ionizeand break down the air. This tends to form an arc, which wastes energyby radiating heat and rapidly burns up electrodes. An arc is inherentlya low voltage, high current device; but it requires a high voltage. tostart it, and, after it has started, the extra voltage must bedissipated elsewhere-.- usually in the high voltage winding of atransformer-thus also wasting energy in the transformer.

'With my method of placing the spark gap in a high-velocity air stream,voltages well above the break-down point of air are used, thus assuringthe eflicient formation of ozone; but the arc is quenched, thus limitingthe current and efiectively minimizing the consumption of energy andpreventing the burning of electrodes or the formation of oxides thereon.Ozone thus produced is quickly removed from the spark to prevent itsdecomposition and is thoroughly mixed with the air, thus to prevent theozone from forming pools or strata in which the odor ofozone would betoo strong. Heretofore, it has been the custom to generate ozone in anapparatus having a solid dielectric to prevent sparking. I have foundthat, in the apparatus hereafter described, sparking is advantageous ofitself and that it assures the efficient formation of ozone, since therequisite high voltage is assured at the formation of each spark.Furthermore, all of the voltage is applied to the air rather than toglass or some other solid dielectric; therefore the voltage required islower and can be supplied by less expensive electrical equipment, andthere is no energy lost in the solid dielectric.

A further object of my invention is to provide air conditioningapparatus in which nascent oxygen is formed in the air to be purified;This nascent oxygen is extremely active chemically and so is useful inpurifying air. However, it is so unstable as to exist only for aninstant and must be used where it is formed.

A further object of my invention is to provide air conditioningapparatus which produces, by means of a quenched spark gap, a maximum ofultra-violet radiation of those extremely short wave lengths whichproduce ozone, and a minimum of long wave length ultra-violet radiationwhich decomposes ozone. Quenching not only increases the production ofshort wave radiation, but it allows said radiation to penetrate furtherinto the air instead of being absorbed by the high temperature envelopesurrounding an unquenched arc. Quenched sparks tend to scatter, thusmaking it unnecessary for the ultra-violet radiation to travel far toreach all particles in an air stream thru which said sparks passtransversely.

A further object of my invention is to provide an ozone generatorutilizing precooled air. Air is heated by compression. Heated air is notas effective in producing ozone or in quenching the gap as is coolerair. Furthermore, the therapeutic value of the treated air is enhancedby precooling. If desired, said air may be cooled in a chamber whichalso serves as a muiller, or a separate mufller may be provided.

A further object of my invention is to provide air conditioningapparatus in which water can be vaporized and mixed with the air. Thiswater vapor is useful not only in increasing the humidity of the air butit also seemingly makes both ozone and ultra-violet radiation moreeffective in destroying bacteria. It has also been found that the odorof ozone is much less noticeable in moist air than in dry air.

A further object of my invention is toprovide means for introducingwater into the air in small quantities, said means not having orificesso small as to be easily clog ed. This is accomplished by forcing waterunder pressure thru an orifice into a chamber of substantially quiescentair that is also under pressure. Thus, water is forced thru said orificeby a differential pressure which, being relatively low, requires arelatively large orifice; the water is so thoroughly atomized as toinsure vaporization; and the amount of water used can be very accuratelycontrolled.

A further object of my invention is to provide air conditioningapparatus which can be built cheaply and which is suificiently portableto be especially adapted for use in motor vehicles, trains, airplanes,and the like. In permanent installations, power for the spark gap can besupplied cheaply and convenientlythru a transformer from a power line.In portable installations, power for the spark gap can be best suppliedby a spark coil operated from a battery. A wellquenched gap is desirablefor portability since it requires so little power.

A further object of my invention is to provide air conditioningequipment utilizing a. quenched spark gap in which the electrical systemis designed and arranged to produce frequencies of such character as notto produce radio interference. I am able to do this with the naturalcharacteristics of the circuit, in some instances without the use ofspecial coils and condensers, and in other instances, I provideadditional inductance and capacity by appropriate agencies. I havenotedthat a high frequ y spark rated from a quenched gap persists evenin the presence of air blowing between the electrodes at high velocity.Said sparks tend to follow a straight line, and their paths are notdistended as far as would be a continuous are.

A further object of my invention is to provide air conditioningapparatus suitable for use with any circulating system for air providedwith temperature and humidity controls and cleaning or washing devices.

Further and other details of my invention are hereinafter described withreference to the accompanying drawings, in which:

Fig. 1 is a. diagrammatic section of a motor coach showing a typicalinstallation in which my invention is used in conjunction with anelectrical heating device;

Fig. 2 is a diagrammatic illustration of a nozzle directed towardselectrodes illustrating the manner in which the air jet distends thepathof the sparks;

Fig. 3 is a transverse section taken on the line 3-3 in Fig. 2, andillustrates the manner in which the quenched sparks tend to extend thrusubstantially the entire jet, even after it has diverged substantiallyafter leaving the nozzle Fig. 4 is a diagrammatic illustration of amodification of my invention in which a part of the nozzle is brokenaway to disclose a siphon-andwick means for introducing liquids into theair stream;

Fig. 5 is a diagrammatic illustration of another modification of myinvention in which the electrodes are shaped advantageously todistribute the electrostatic field to facilitate effective sparking;

Fig. 6 is an elevation illustrating the manner in which the structuresare arranged to attain the purposes of my invention;

Fig. 7 is an enlarged detail view of the nozzle and fragments of the airand water supply means, with portions thereof shown broken away todisclose the internal construction;

Fig. 8 is a diagrammatic illustration of the electrical circuitembodying my invention; and

Fig. 9 is a diagrammatic illustration of a modification of my inventionin which a thermostatic control is shown mountedon the cooling tank and,connected to said control, a switch arranged in a branch of the circuitof Fig. 8, with the off position of said switch being shown in dottedines.

Referring to the drawings which form a part of this specification, I isan air pump, shown more clearly inFig. 6, 2 is an electric motoroperatively connected to said air pump by means of a shaft 3 which shaftcarries fixedly secured near its outer end a pulley wheel 4 and theidler pulley wheel 5 adjacent thereto. Said motor and said air pump maybe supported by any convenient means (not shown), and said motor may besupplied by any suitable source of power.

An air intake pipe 6 is adapted to receive air to be purified and toconduct the same to said air pump. Said air is compressed and forcedfrom said air pump thru pipe I to the cooling chamber 8 which may, ifdesired, be positioned in a-brine tank 9 having immersed thereinrefrigerating coils l0. Said coils may be connected to a motor-drivenpump II and to the storage tank l2 and the expansion valve 13 bysuitable pipe means. Said motor driven pump may compress a refrigerantin said tank l2 and said refrigerant expanding through said expansionvalve will then absorb heat from the brine in the brine tank 9. Anysuitable refrigerant, such as ammonia, may be used.

Air release valve l4 is'operatively connected to' said cooling chamber8- by meansof the pipe l5. Air is conducted from saidlcooling chamber bypipe l8 to a T-member l1, thence thru pipe I8 to nozzle I 9, which maybethreaded on the pipe l8.

A belt 20 operatively connects either pulley wheel 4 or pulley wheel topulley wheel 2|, which is fixedly secured to shaft 22 of water pump 23.It will be understood that, when said belt connects pulley wheel 4 topulley wheel 2|, both will be rotated, but, when said belt connectspulley wheel 5 to pulley 2|, neither will rotate.

The pump 23 is referred to forconvenience as a water pump, but it shouldbe understood that other liquids may be used therein if desired. Saidwater pump is adapted to draw water from tank 24 thru pipe 25 and todischarge said water thru discharge pipe 28 to a needle valve 21. As isshown more particularly in Fig. '1, said needle valve comprises a member28 into which is threaded said discharge pipe 26 at one side thereof.

one side of said T-member I1 to the interior .of

pipe l8 thence to the nozzle l9. Said pipe 35 may be supported in saidT-member by the threaded bushing 36 engaging packing means 31. Saidpacking means is adapted toprevent leakage of air around said pipe 35.

Said pipe 35 is supported near the end thereof by a disc 38 which maybepress-fitted into said nozzle l8. Said disc 38 has a plurality of holes39 arranged near itsperiphery, said holes being adapted to permitpassage of air into the eompression'chamber 49. The end of the pipe 85is partially closed by the disc 4| in the'central portion of which is anorifice 42. Said orifice is adapted to admit water or other liquid tothe compression chamber 49. Said disc 4| may, if desired, be soldered tothe end of pipe 35. Said nozzle l9 may be firmly pressed into a hole inthe insulating member 43.

A plurality of electrodes 44 may also be pressfitted in said insulatingmember 43, said electrodes being positioned to form a spark gap 45 infront of said nozzle l9. Said nozzle I9 is provided, at its outer end,with an orifice 45 adapted to direct a jet of air 41 thru said sparkgap. Said electrodes 44 may be made of any suitable material. I havefound Monel metal to be satisfactory. For the purpose of forming a sparkgap, said electrodes 44 are directed substantially toward each other andare spaced apart a distance depending on the electrical characteristicsof the circuit hereafter described. I have found a space of one halfinchto be satisfactory, although it can be more or less.

Said electrodes 44 may be connected to a transformer 49 by wires 58'which may, if desired, carry insulating material 48. Said transformer 49carries binding posts 5| adapted for connection to a source ofelectrical power. Surrounding said nozzle and said electrodes aprotective tube 52 is positioned. Said protective tube may be made ofany convenient material such as wood fiber.

An alternative structure adapted for use with a battery 53 as a sourceof power is schematically shown in Fig. 8. When the switch 54 is closed,current from said battery will flow thru the primary'winding 55 of saidtransformer 49 and thru the magnetic interrupter 55 thence back tobattery 53. Said interrupter is adapted to repeatedly make and breaksaid primary circuit by means of contact members 51. If desired, saidinterrupter 56 and said transformer 49 may be integrally constructedinthe form of the well known spark coil. Said transformer 49 is providedwith an iron core 58. Between said primary winding 55 and secondarywinding may be placed a metal shield 6| which may, if desired, beconnected to ground by the wire 59.

As hereinafter described, it is desirable to use a substantial amount ofinductance and capacity in conjunction with said spark gap 45. I preferto .use a transformer which supplies sufiicient ing of the transformeris unusually low, or if the resistance of said winding is too high, itmay be desirable to add capacity to the circuit and this may be done byarranging a condenser 83 as shown in Fig. 8. I have used a capacity ofabout Ill micromicrofarads as condenser 63. The resistance of saidsecondary winding is represented at 62.

As shown in Fig.'9, as an alternative structure, if desired, athermostatic member 86 may be fixedly secured to cooling chamber 8 byrivets 61. Said thermostatic member is adapted to engage lever 88 whichis operatively connected to lever 69 of snap switch 10. As shown bydotted lines, when said thermostatic member is heated by heat from saidcooling chamber 8,

I it moves said lever 59 to the oif position. Said snap switch 10 may beconnected to the primary of the electrical circuit in such a way as tointerrupt the current therein when in its off" position.

As is shown in Fig. 4, an alternative means for introducing water orother liquid .into the air stream comprises a bushing 1| threaded intoT-member 12 which together with nozzle member 13 is adapted to replacenozzle [9. Threaded into said bushing 1| is a reservoir 14 provided witha tube 15 leading to the bore of T-member 12. Said tube is provided withan opening 15 near its lower end. If desired, a wick 11 may be insertedin said tube in such a way thatits lower end is immersed in liquid 18contained by,

said reservoir 14, the upper end of which may extend into the bore ofT-member 12.

A preferred shape of the end portion of elecgodess 44 is showndiagrammatically at 44a in My invention has been described andillustrated for use with the room 88. A typical installation embodyingmy invention is shown in Fig. 1 wherein the purified air from the nomlcThe exhaust gases from said motor are dis-' charged thru pipe 85 intothe air.

The foreign matter which ordinarily befouls the air within a motor coachis of a composite nature. Some of it is readily neutralized by ozone,whereas other constituents, such as unburned fuel and tobacco or othersmoke, can be rendered innocuous only by heating them to a hightemperature, preferably in the presence of ozone or nascent oxygen.Other foreign material, such as some dusts, will not be chemicallychanged by a brief contact with electric sparks, but it will besterilized thereby.

In my invention, molecular oxygen and other elements are dissociated bythe heat of the sparks or the electrostatic field associated therewith.The resultant nascent atoms are very active chemically and are,therefore, very useful in purifying air. However, they exist for only abrief period of time and must be utilized promptly, within a shortdistance from the place where they are formed, otherwise they willrevert back to some molecular form uselessly, or they will form lessactive molecules such as ozone. Although less active than nascentoxygen, ozone is useful because it is carried out into the air of themotor coach and there destroys bacteria and odors.

The way in which the sparks of the quenched gap in my invention arescattered throughout the air jet is shown in an enlarged view in Fig. 2and Fig. 3, wherein the sparks are indicated by the numeral 89. Theserapidly recurring sparks constantly shift their paths so that the airjet is thoroughly sprayed with them. Thus the nascent atoms are utilizedto purify the air in the immediate vicinity of their formation, andsubstantially all particles of *said air are subjected briefly to theheat of said sparks. Inasmuch as the air in the motor coach recirculatesthru my device, if any foreign matter should escape the action of thesparks and ozone and nascent oxygen on its first trip therethru, it willbe again subjected to said action.

While my invention is shown as being used in conjunction with theheating member 88, it is to be understood that it might similarly beused with any other form of air cooling, cleansing, or dehumidifyingmeans, and a blower, not shown, for circulating said air may, ifdesired, be included as a part of said means.

The operation of my invention is asfollowsz The transformer 49 and themotor 2 are simultaneously connected to a source of power. An areimmediately forms across the spark gap 45. This is a continuous, flamingare and, if long continued, it would rapidly consume the electrodes.Also, said continuous arc is produced by a low voltage which does notionize the air to produce ozone. A continuous arc causes ozone todecompose into molecular oxygen. Furthermore, the ultra-violet radiationfrom such a continuous arc is of a kind which brings about thedecomposition of ozone.

However, in my invention. this continuous arc exists for only a briefperiod of time. When and muffler 88 and pipe 8'! the jet of air from theair pump attainsits full velocity, it quenches said are so thatthereafter only a, series of intermittent sparks pass between theelectrodes, or from the electrodes to the surrounding ionized air. Thesehigh frequency sparks are caused by rapidly oscillating electricalcharges in the. circuit that includes the spark gap; when the are ismoved or broken by the air jet, the resultant electrical phenomena causerecurring sparks at frequencies determined by the electricalcharacteristics of said circuit.

Whether power is supplied to the transformer from an alternatingsource,.or whether a battery and interrupter lsused in the primary, thevoltage in the secondary will be pulsating. The intermittent sparksherein described are produced by said pulsating voltage but they areordinarily of much higher frequency than said pulsations. I have foundit advantageous to use a circuit in connection with said spark gaphaving such inductance and capacity that said sparks recur as frequentlyas 25 million times or more per second, although it is notnecessary thatsuch a high frequency be used. I have found that less interference withradio receivers is caused thereby than when said frequency is lower.

These high frequency sparks may be referred to as quenched arcs orquenched sparks, and: the process of quenching the continuous arc toproduce said sparks is known as quenching th g p It willbe understoodthat said intermittent sparks will not all recur at the same frequency;several frequencies may be produced. This is due to the fact that thecurrent that flows thru the spark gap may follow any of severalalternative paths, for example, thru the capacity of the windings, thruthe capacity between wires, or thru coupled circuits; that is, thecircuit usually has more than one degree of freedom. I deem this to beadvantageous in that it causes the sparks to spread out more; the higherfrequency sparks passing directly across the spark gap, the lowerfrequency sparks being more distended by the air Jet.

If the velocity of the air thru the gap is sufficiently high, said gapwill be almost completely quenched-only high frequency sparks will beformed. If the velocity of said air is lower, a continuous arc will beformed but it will'be distended away from said Bap. while high frequencysparks will pass more directly across said gap. Thus," as applied to aspark gap, quenching is a relative term; a gap may be well quenched oronly partially quenched.

In my invention, I prefer to have the gap well quenched, since there arethenmore of the beneficial results with less energy consumption, andthere ls-no noticeable pitting or oxidation of the electrodes. Moreenergy in the air between electrodes accompanies said high frequencysparks than with low frequency sparks or a continuous are; therefore, mypurposes are accomplished with little current and consequent eliminationof pitting of the electrodes.

It is frequently desirable to introduce moisture I into. air; thisisespecially desirable when ozone is used because the odor of ozone isless objectionable in moist air. Also, both ozone and ultravioletradiation are more effective in killing bacteria in the presence ofwater vapor. However,v

same time, it is advantageous to introduce said water underpressure inorder that it, may be better controlled and to assure vaporization.However, to introduce a small quantity of water at high pressurerequires an orifice so small that it is easily clogged. I

I have found that if water under considerable pressureis forced thru theorifice 42 into air at slightly less pressure in the compression chamber40, a comparatively large orifice can be used, because water flows thruit only because of the small differential pressure between said waterand said air, and said water is thereby sothoroughly atomized and mixedwith said air that it immediately vaporizes. The amount of said watercan be accurately controlled by needle valve 21.

Ozone is more readily formed from cool air than from warm; cool air morethoroughly quenches a spark gap; and cooled air from my device has apleasant, refreshing efiect when breathed that is different from theeffect of any other airI have observed. Said air appears to haveimportant therapeutic value for beasts and birds, as well as humans. Itis likely that said therapeutic value is due chiefly to ozone; but noneof the common bad effects of ozone, such as headache, are produced byair from my-invention even when dosages sufllciently large to producemarked beneficial results are used. Cooling the air also retardsdecomposition of ozone therein.

' I have found that when the compressed air is passed consecutively thrutwo or three small cooling tanks, such as are shown at l in Fig.9, it isbetter cooled and gives better results than when only ,one such tank isused. Accordingly, it is more advantageous to cool said cooling tank 8thoroughly by immersing the same in a refrigerating'brine tank, as isshown in Fig. 6.- Said cooling tanks serve the further purpose of actingas a muiiler to absorb pulsations in the air that would otherwiseproduce objectionable sound shown in Fig. 5, although this shape is notnecessary and ordinary pointed electrodes operate sati'sfactorily.

By the means and method described, I utilize ozone in a peculiarlyeffective way to purify air, andlto remove odors therefrom; I furtherpurity and deodorize said air by combustion and by ultra-violetradiation; and I accomplish this result by means that are cheap andunusually free from trouble, not being affected by dust or moisture, andthat require very little power to operate. 6

My invention can be used in damp cellars and in refrigerators whereodors are commonly found and where other ozone generators will notoperate because 01' the moisture.

I claim:

1. In air conditioning apparatus, means for treating the air in achamber comprising air circulating and recirculating mechanism adaptedto withdraw continuously a portion of the air in said chamber andreintroduce it; means for prober; a. pair of electrodes arrangedadjacent but.

to the sides of the jet' thus produced-fan electric circuit connected tosaid electrodes; mi'aans'i'orv impressing across said electrodes 'anelectrical potential sufliciently high to produce contmuous flaming areextending across'the path of said jet; and means foracceleratingthejfair of said jet to such a velocity as tochanges'aid'flaming arc to a quenched are which is adapted to form, beextinguished, and to reform at high fre'-' uency. f

2. In air conditioning apparatus, means for treating the air in achamber comprising air circulating and recirculating mechanism adaptedto withdraw continuously a portion of the air in said chamber andreintroduce it; means for producing a jet of said air directed into saidcham-. ber; means in connection with said jet producing means for theinspiration of moisture into said jet in predetermined quantities; apair of electrodes arranged adjacent butto the sides of. the jet thusproduced; an electric circuit connected to said electrodes; means forimpressing across said electrodes an electrical potential sufiicientlyhigh-to produce a continuous flaming are extending across the path ofsaid jet; and means g for accelerating the air of said jet tosucha'velocity as to change said flaming arc to a quenched are which isadapted to form, be extinguished, and to reform at high frequency.

3. In air conditioning apparatus, means for treating the air in achamber comprising air circulating and recirculating mechanism adaptedto withdraw continuously a portion of the air in said chamber andreintroduce it; means for producing a jet of said air directed into saidchamber; means in connection with said jet producing means forthe'introduction of moisture into said jet in predetermined quantities,said moisture introducing means functioning with the water being underhigher. pressure than the air; a pair of electrodes arranged adjacentbut to the sides of the jet thus produced; an electric circuitconnectedto said electrodes; means for impressing; across said electrodes anelectrical potential sufficiently high to produce a continuous flamingare extending across the path of said-jet; and means for acceleratingthe air of said jet to such a velocity as to. change said arc to aquenched are which is'adapted to form, be egrtinguished, and to reformat high frequency. 1

4. In air conditioning apparatus, means for treating the air in achamber comprising ancir culating and recirculating mechanism adapted towithdraw continuously a portion of the air in said chamber andreintroduce it; means for producing a jet of said air directed into saidchamber; refrigerating means associated with said jet' producing meansfor cooling the air in advance of said jet; a pair of electrodesarranged adjacent but to the sides of the jet thus produced: an electriccircuit connected to saidelectrodes: means for impressing across saidelectrodes an 5 electrical potential suiiiciently high to produce acontinuous flaming are extending across the path of said jet; and meansfor accelerating the air of said jet to such a velocity as to changesaid flaming arc to a quenched arc which is adapted to form, beextinguished, and to reform at high frequency.

5. In air conditioning apparatus, meanslfor treating the air in achamber comprising air circulating and recirculating mechanism adaptedto withdraw continuously a portion of the air in said chamber andreintroduce it; means for producing a jet of said air directed into saidchamber; refrigerating means associated with said Jet producing meansfor cooling the air in advance of said jet; means in connection withsaid jet producing means for the introduction of moisture into said Jetin predetermined quantities; pressure inducing means for liquid forsupplying said moisture and for said air, said means supplying saidfluids to said jet producing means at more or less constant velocity andat predetermined relative pressures, the pressure of the liquid beinghigher than that of the air; a pair of electrodes arranged adjacent butto the sides of the Jet thus produced; an electric circuit connected tosaid electrodes; means for impressing across said electrodes anelectrical potential sufficiently high to produce a continuous flamingare extending across the path of said jet; and means for acceleratingthe air of said jet to'such a velocity as to change said flaming arc toa quenched are which is adapted to form. be extinguished, and to reformat high frequency.

6. In air conditioning apparatus, means for treating the air in achamber comprising air circulating and recirculating mechanism adaptedto withdraw continuously a portion of the air in said chamber andreintroduce it; means for producing a jet of said air directed into saidchamber; a pair of electrodes arranged adjacent but to the sides of thejet thus produced; an electric circuit connected to said electrodes;means for impressing across said electrodes an electrical potentialsufiiciently high to produce a continuous flaming arc extending acrossthe path of said Jet; and means for accelerating the air of said Jet tosuch a velocity as to change said flaming are to a quenched are which isadapted to form, be extinguished, and to reform at high frequency, saidcircuit including suflicient inductance and capacity that a quenched arcis produced in which the mostenergetic sparks recur at a frequency inexcess of two megacycles per second.

FRANK W. LOCKE.

